Electric vulcanizer



Nov. 16, 1937. v E. c. RANr-:Y

ELECTRIC VULCANIZER Filed sept. 15, 1935 5 Sheets-Sheet l Nov. 16, 1937.E C, RANEY 2,099,499

ELECTRIC VULCANI ZER Filed sept. 1:5, 1935 s sheets-sheet 2 v www,

Nov. 1 6, 1937. l.;- Q RANEY 2,099,499

ELECTRIC VULCANIZER Filed Sept. l5, 1935 3 Sheets-Sheet 3 fg Hlm. n

Patented Nov. 16, 1937 Y i Y y iUNITED STATES PATENT oFFlcE ELECTRICVULCANIZER Estel C. Raney, Columbus, Ohio, assigner to RancoIncorporated, a corporation of Ohio Application September 13, 1935,Serial No. 40,466

7 Claims. (ci. 21a- 19) This invention relates to an improvedelecstatically operated switch means whereby the trically heatedvulcanizer for use in the repair thermostatic element of the switch andthe vulof rents, tears or openings in rubber or rubbercanizing surfaceof the Vulcanizer are malncontaining bodies, such as motor vehicletires, tained at substantially the same temperatures f inner tubes fortires, and the like. during all phases of operation of the vulcanlzer.

It is the object of this invention to provide The present inventionconstitutes a continuaan electric vulcani'zer wherein heat is appliedtion-in-part of my prior application, Serial No. to the vulcanizingsurface of the vulcanizer until 709,385, illed Feb. l, 1934. thetemperature of the surface reaches a prede- For a further understandingof the invention,

l0 termined point whereupon the heating of the reference is to be had tothe following description 10 surface is automatically discontinued ormodiand the accompanying drawings, wherein: lied. Fig. l is aperspective view of an electric vul- An outstandingobject of theinvention resides canizer` constructed in accordance with the inproviding an electrically heated vulcanizer present invention, vthestationary and movable Y l5 having a heater unit including a pluralityof reshoes of the vulcanizer being shown in their 1D sistance 'or heatercoils of different electrical 'separated or open positions; valuesincombination with a thermally operated Fig. 2 is a vertical sectionalview taken through switch mechanism and a source of current supthevulcanizer and disclosing the stationary and ply, whereby thevulcanizing surface of the vulmovable shoes thereof in closed order andin 20 canizer may be quickly raised to a predeterengagement .with therubber article undergoing y20 mined vulcanizing temperature by theheater vulcanization;

coil having the lower resistance value whereupon Fig. 3 is a horizontalsectional' view on the the heater coil having the higher resistance isplane indicated by the line III-#III of Fig. 2; automatically connectedin series with the rst Fig. 4 is a vertical sectional view on the line3.', said coil to reduce the heating effect of the heat-A IV-IV of Fig.2; 25 er unit on the'vulcanizing surface to retard the Fig. 5 is adetail vertical sectional view disnormal cooling of the surface so'thatthe mateclosing the thermostatic latch means for retainrial undergoingvulcanization will be thoroughly ing the switch mechanism in a positionof circuit heated at the proper temperature to assure comclosure; 3')plete vulcanization thereof. Fig. 6 is a vertical sectional view takenthrough 30 Another object of the invention is to provide the resistorbase of the vulcanizer and disclosing. in an electric vulcanizer aheating unit having the bi-metllic thermostat for controlling the a pairof heater coils of different resistances and operation of the resistorswitch;

a switch for controlling the flow of current Fig. 7 is a detailsectional view taken through, :35 through said coils whereby when thevulcanizer the resistor coils; 30 is not in active use current isdirected through Fig. 8 is a diagrammatic view of the circuit both coilsso that the vulcanizing surface may arrangement in which the resistorcoils arebe maintanedat a temperature slightly below situatedf' V thevulcanizing temperature with the consump- Fig. 9 is a verticaltransverse sectional view i 11) tion of a comparatively small amount ofcurrent on'the plane indicated by the line IX--IX of 40 and whenvulcanizing is to be accomplished the Fig. 3; l

switch maybe operated to direct current through Fig. l() is aperspective View of the vswitch the low resistance coil whereby thevulcanizing mechanism; f surface is quickly raised to a predeterminedvul- Fig. ll is a horizontal .sectional view on the 1R canizingtemperature, whereupon the switch plane indicated by the line XI-XI ofFig. v6; 45

Aautomatically operates to direct current through Fig. l2 is aperspective view of a heat applying both coils to reduce the heatingeiect of the plate used whenaplain patch is -tobevulcanized heating uniton the surface. My improved vulcanizer, in the preferred form It isstill another object of the invention to thereof illustrated in theaccompanying draw- 1' provide in an electric vulcanizera-thermostatiings, comprises a frame I, which may consist 90 callyoperated switch wherein the thermostatic of a pair of duplicate,reversely arranged metalelement is shielded frorndirect radiation ofheat lic stampngs 2, the hitter being formed t0 infrom the heaterelement of the vulcanizer, clude vertical side walls 3 which terminateat It is also the*v object of this invention to protheir lower edges inVoutwardly and laterally di- .35 vide an electric vulcanizer having athermorected base flanges 4 and along their upperedges 55 in outwardlydirected normanni supporting flanges 5. The rear vertical edges of thewalls 3 terminate in out-turned vertical flanges t which 'possess asomewhat wedge-shaped configuration,

enabling the flanges t to be removably received, i

connection of thevvulcanizer frame. to a suitable vertical supportingwall. Again, the vulcanizer may be mounted on the upper surface of atable, bench or the like byl the flanges ll. I

Securedto the flanges il of the vulcanizer frame is a stationaryresistor casing 'l which is formed to include a substantiallyrectangular metallic member il formed centrally with a depending collard and a vertical axial opening lil, together with ,depending marginalwalls il. Arranged to cover the bottom ol the housing member 4tis aaccanto T an opening 28 formed in the front marginal wall.

il or fthe metallic base member t.

Secured to the front wall of the member B is a yertically disposedmetallic plate 29 which isalso providedwith an opening in registrationwith the opening 28 for the receptionof the extensions 2li. The front ofthe plate 29 carries a stationary angle member 30, to which is secured asubstantiallylJ-shaped. shelf 3l of an insulating material and theextensions 21 overlle the notch 'or recess 'formed in the shelf. vAsshown in Fig. 6, the

resistor unit, which comprises the coils 2t and j this supported withinthe chamber it by a pad metallic closure plate l2 and disposed betweenthe plate l2 and the anges El of the vulcanizer frame ls a plate it of asuitable heat insulating ma-v terial, the plates i2 and i3 beingprovided. with axial openings it which register with the' opening ill inthe housing member, d.' These parts are retained in assembled order bythe provision of vertical screws l5 which are arranged in the cornerportions oi the resistor casing and have their lower threaded endsreceived within threaded openings provided inthe frame anges t. -By

this construction, an internal ring-like chamber i6 is provided inthehousing member d for the reception of the electrically heated resistorcoils of the vulcanizer.

stantia-lly ring-shaped unit 'comprising an upper Athin metallic plateil of high thermal `conductivity an against the under side of which isplaced a thin sheet it of mica or other dielectric substance. Contactingwith the under side Aci the dielectric sheet it is an asbestos ring l@inwhich is embedded a spirally arranged, helically wound,.primaryresistance coil 2d; vEngaging the under side of the ring it and the coil2t is a second or intermediate ring-like disk il of mica, and disposedto engage with the under side of the disk 2l is' a second asbestos ringit in which-is embedded a spirally disposed, heli- ?li of insulatingmaterial, the latter being disposed. within the lower portion of thechamber iii and is arranged between the plate it and the resistanceunit.

Carried by the Ishelf 3i are binding posts 33, dfi, and 35. Electriccurrent 'from a suitable source of supply, such as a commercial powercircuit, the lines of which are indicated at` 36,

has connected therewith a conductor lil' which extends to the` bindingpost 33, which is connected by a lead 'ttt with the'seconda'ry, highresistance coil 2d. From the coil 23, the current is directed, vwhen thevulcanizer is inactive, through a lead 39 which extends to the primarycoil 2li and a lead 4ll extends from the other end oi the coil 2t to thereturn line of the circuit tti. The lead 3Q, which unites the coils' and23, is connected with the post 34 by means of a conductor ttl Normally,therefore, current may be said to pass from thesource of supply by wayof the conductor 3l, the lead 3d, thence through the high resistancesecondary coil 23; the lead 39, thence throughthe primary coil 2li andback to the source of 'supply by way of the lead tit. The coil t3 byreason of its high resistance value .becomes mildly heated in order thatthe heat transmitting parts of the vulcanizer may be maintained at asomewhat elevated temperature cally wound. secondary resistor coil tt,whichl possesses greater resistance values to the flow of electriccurrent than the primary.coil 2d. To retain the coil 23 in place, is abottom sheet i2t of A mica, which possesses the same general dimensionsas the upper sheet it. The intermediate sheet il possesses a greaterintel diameter than the sheets ld and 24 in order to provide for thereception of a ceramic insulating ring 25. To hold these parts togetherin rigid assembly, the metallic plate l'i is provided with downwardlydirected lingers 26, which are struclr 'from lthe inner and outer edgesof the disk-like plate lll. These ngers have their lower ends bent toengage with the bottom surfaces of the mica sheet between successiveoperations of the vulcanizer, and principally to lengthen the time thatthe vulcanizing shoe is maintained at a vulcanizing temperature afterthe low resistance coil 2li has been rendered less active after heatingthe vulcanizing shoe to a predetermined temperature. The heat of coil 23also prevents the vulcanizer from cooling to too great an extent betweenvulcanlzing operations so as to retard its rapidity of operation.However, when a vulcanizing operation is started, the secondaryresistance coil 23 is shunted, lso that all of the current will flowthrough theprimary resistance coil4 20,

`which becomes highly heated and will quickly coil 23 when thevulcanizer is to be used, there is carried by the plate 29 a forwardlyand hor- 2t so that the various parts of the resistor may i be assembledandv maintained as a unit.

I'his unit -is vlpositioned in the chamber l@ of the resistor casingandVsurrounds the collar d of the housing member @,wlth the metallic platel1 of the Aresistor unit toward the bottom suraxis alorded by the stud43.

face of the at upper wall of the member t and separated from the wall bya thin ring-like disk of asbestos lla.

24 are, as shown in Fig. 3, provided with laterally disposed extensions2l which project through The mica sheets it, 2l and izontally projectingstud :43, which is located beyond the corresponding edge of the shelf.3i. The stud 43 passes through registering apertures provided inupstanding ears M of a manually closable switch 45, the switch rockingabout the In this instance, the switch is provided with a depending armd ci a suitable dielectric substance and is mounted for oscillation in aslot provided in the lower wall of a switch covering shell 41, which isdetachablyponnected as at '4B to the metallic base 8.

Formed with the switch 45, as a unitary part the base 8 rather `thandirectly from the heating .end an upst'anding post 50 of insulatingmaterial, and to the upper end of which is swivelly v connected forswinging movement -a bridge 5I. This bridge is adapted, when, the switchis closed, te engage with the lower.ends of the binding posts 33 and 34in order to shunt the resistor coil 23, as shown diagrammatically inFig. 8.

While the switch 4is adapted to be manually closed, means are providedfor retaining the same in its position of closure and automatically ef'fecting its release or opening when the vulcanizer attains apredetermined temperature. This is accomplished by providing. the switchwith an upstanding arm 52 which terminates at its upper end in a nger53, the latter being formed for engagement with a shoulder 5a formed inconnection with a metallic stamping 55. This stamping is secured to theouter end of a bi-metallicthermostatic strip 55 which has its inner endssecured as at 51 to the metallic base 8, the strip occupying atransverse recess 56a formed in the lower surface of the upper wall ofthe base 8 immediately adjacent to the resistor unit,'the stamping 55projecting 'through an opening 56 formed in the forward marginal wall II of the base 8 in alignment with the recess in which the strip 56 ispositioned.

The recess 56a is of a depth somewhat greaterv than the thickness of thethermostatic strip 56 and is provided near lits rear end with a shelfwhich forms a base for the reception of the thermostat. The plate l1 andasbestos disk extends across the recess 56a as shown in Fig. 9 andengages the under side of the upper wall of the base 8, leaving an airspace between the under surface of the thermostat and the asbestos disk.This construction is employed to provide for the transmission of heat tothe thermostat by conduction through element. In this manner, the actualtemperature of the base 8 affects the thermostat.

Connected with the outer .end of the stamping 55 is the upper end of acoil spring 59, the latter havingl its lower end connected with anadjusta-i ble header post 60 which is carried by a laterally directedwing 6i forming a part of the switch 45.

Normally, the tendency of the spring 59 is to oscillate the switch sothat the bridge 5i will be moved out of contact with the terminal posts33 and 34. However, upon manual operation of the switch, the latter isrocked about the axis of the stud 43against the resistance of the spring59,

thereby bringing the bridge5l into circuit cornpleting contact with theterminal posts 33 and 34.

The switch is retained in this position of closure by the engagement ofthe finger 53 on the arm.52 with the shoulder 54 of the stamping 55.This engagement is rendered positive by the presence of the spring 5S.When the switch is thus closed, the full flow of current takes placethrough the primary coil 20 until the vulcanizer attains a pre-Adetermined temperature. At this time, the ther- A mostatic strip 56responds to the elevated temperatures and flexes sufficiently, inopposition to the force of the spring 5 9, to free the shoulder 54 fromengagement with the nger 53; Then, in response to the action of thespring 58, the switch oscillates to assume its open position. Theoperation of the main spring 56 may be supplementedby an auxiliaryspring 62 which is carried by the stud 43vand engages with the switcharm 46, the tendency of the spring 62 being to maintain the switch inits open position. The entire vulcanizer may be disconnected fromthe-source oi' electrical supply through the usual plug and socketfittings.

Removably positioned'on the upper surface of'.

the base member 6 is a heat applying shoe plate 63. This plate in theform thereof illustrated in Fig'. 2, is composed of a heat conductingmetal, such' as aluminum alloy and rests directly on the base 8 toreceive the heat of the latter. When the 'vulcanizer is employed torepair tire inner tubes, ofthe type indicated at 64, in the region ofthe air admitting and releasing valves 65 thereof, the plate 63 isprovided with a depending collar 66, which is receivable in the axialopening l0 of the base 6. The collar 66 may be provided with projectionsor shoulders 66a, which are received within bayonet slots formed inconnection with the walls of the opening l0, whereby to positivelyretain the shoe plate against-accidental withdrawal. When the vulcanizeris employed in connection with portions of an inner tube, other than theregion of the valve 65 thereof, a shoe plate 63a, formedv without thecentral opening therein to present a smooth uninterrupted upper surfaceas shown in Fig; 12, is employed. Either of these types of shoe platesmay be substituted for one M anotherat will.

To apply pressure to the rubber article positioned on the shoe platewhile the article is undergoing vulcanization, the verticalside walls 3of the frame is pivotally connected as at 61 with a manually operatedlever 68. This lever comprises a pair .of duplicate sections which moveas a unit for swinging movement in a vertical plane. The spacedintermediate portions of said lever pivotally support as at 69 theU-shaped bail 1D, which has its lower end secured to an upper pressureplate or disk 1l, the under surface of the latter being faced with acushion 12 of compressible or resilient material. .The bail 10 isprovided with an elongated slot 13 which receives the pivot pin 69 ofthe lever 68, thus enabling the pressure plate to adapt itself readilyto the configuration of the rubber article confined between the same andthe shoe plate 63. A spring 14 surrounds the pivotal connection 61 ofsaid lever and is cooperative with the pin 15 carried by said lever sothat the normal tendency of the spring 14 will be to raise the lever toits inactive position, and the outer end of the lever is formed with ahand grip 16 by which the lever may be grasped and moved downwardlyagainst the operation of the spring 112.

To maintain the levers and their associated pressure'disks in theirlowered or pressure applying positions, the frame l is .provided with athreaded bolt 11, which is pivotally mounted as at 16 in'connection-withthe frame i, the pivot 18 being provided with a spring 19, whichoperates on the bolt to swing the same forwardly. The upper end of thebolt receives a manually rotated nut 80, which engages with a washer 8iat its lower end. lBy tightening the nut, the washer 8i willbemaintained in firm engagement with a seat 82 formed in connection withthe upper edges ofthe sections of the lever 68, whereby to maintain saidlever in its lowered position and to securel the desired degree ofpressure on the rubber article undergoing vulcanization. .By looseningthe nut and freeing the washer 8| from engagement with the seat 82., thebolt 11 may be swung to a position clear of the lever, thus allowing thelatter to lift in response to the inuence of its spring 14.

In viewl of the foregoing, it will .be apparent that the presentinvention provides a compact,

reliable and efficient vulcanlzer which is especially adapted for use ingarages, tire shops and aooafeea When the switch is moved to itsposition of closure, it is automatically retained therein and theprimary heating coilis energized for a sumcient period of time until apredetermined vulcanizing temperature is attained. At this point, thethermostatic release mechanism functions to automatically release theswitch and cause it to assume its open position. When the vulcanizer'isinactive, and yet connected with a source of current supply, a minordegree of heating' thereof will take place by the passage of currentthrough the secondary coil which becomes heated to a sullicientdegree toprevent the undesired com plete cooling of the vulcanizer. This enablessuccessive vulcanizing operations to be carried out expeditiously andwith but a minimum loss of 'Without the use of the insulating/memberlila between the heater element and the base, it has been found that oninitial energization oi the vulcanizer when the thermostatic strip'andthe base are at atmospheric temperature the base member assimilates heatmuch morerapidly than the thermostatic strip land consequently when thethermostatic'strip attains the temperature at which it is set to operateto open the switch circuit the temperature of the base is considerablyabove the temperature of the strip and overheating of the materialundergoing vulcanizlng is likely to occur. On subsequent operations thethermostatic strip will have had time to attain the temperature of thebase and the switch will then be operated at substantially the same temperature as thatoi the base. To overcome this difficulty the disk oiasbestos ila, is interposed between the .heating element and the basewhich prevents rapid heat transfer to the base so thatthe heat may beassimilated by the thermostatic strip at the same rate as theh`eat istransferred to the base, so that on initial energization oi thevulcanizer the ,thermostatic strip will always. be

vat substantially the same temperature as the base member and the switchwill operate at a substanf tially constant cut-out temperaturewhetherthe apparatus is warm from prior use or warm from heating oi thehigh resistance coil.

While l' have described what I consider to be the preferred form of thepresent invention, nevertheless it will be understood that the latter issubject to certain modiilcation and variation from the form hereinspeciically illustrated and scope oi" the invention as the latter hasbeen dev fined in the following claims.

What isI claimed is:

l. in an electric vulcanizer, a' shell having a relatively thickvulcanizing wall and a recess therein, a heating element for heatingsaid wall and positioned adjacent to said wall, a switch ior controllingthe flow of curre nt through said Yheating element and positionedenteriorly ci the shell, a thermostatic element located in said recessso that said thermostatic element' is substantially between the heatingelement and said wail, and a member of heat insulating materialinterposed between said heating element and said wall.

2. In an electric vulcanizer, a shell having a relatively thicklcanizing wall and an elongated recess therein, a eating element forheating said walland positioned adjacent to said wall, the surface ofwhich bridges said recess, a switch positioned on the exterior of saidshell for controlling the lflow of current through the heating elementiand a thermostatic element for controlling the operation of the switchpositioned l Within said recess in heat receiving relation to the wall.

3. In an electric vulcanizer, a heater unit comprising a casingV havinga vulcanizing wall, an electric resistance arranged within said casingand adjacent the vulcanizing Wall thereof, a main n viding for currentflow through a portion oi the circuit ior said resistance, a shuntcircuit prototal resistance, a normally open switch for said shuntcircuit and mounted on the exterior of said casing, spring meansnormally maintaining said switch in its open position, manuallyoperated` means for moving said vswitch against the resistance -of saidspring means to its positionof circuit closure, a spring latch engagingsaid switch .for retaining the latter in its position of circuit fclosure, and a thermostat, 'thermally associated with the casing andextending beyond the casing, the extended end of the thermostat beingrarrangedto actuate said latch to release said switch and restore thesame to its normally open posi- Ition when said casing has 'been heatedto substantially a predetermined temperature.

fi. in an electric vulcanizer, a heating unit cornprising a, casinghaving a vulcanizihg wall, primary and secondary resistors mountedwithin said casing in heat transmitting relationship with thevulcanizing wall thereof, a main electric cirycuit in which saidresistors are normally situated `in series, a shunt circuit connectedwith saidl main circuit and operable when completed toy divert currentfrom the secondary resistor and .to pass current solely through theprimary resistor, a manually operated, normally open switchv for saidshunt circuit, said switch being detachably mounted onthe exterior ofsaid casing, a spring latch engaging said switch for positivelyretaining the same in its position of circuit clo. sure, and abi-metallic thermostat arranged in said casing and extending through thecasing, said thermostat being adapted' to release said latch to opensaid switch to destroy the shunt circuit when said casing attains asubstantially predetermined temperature.

5. in an electric vulcanizer, a casing having a relatively thick wall,adapted to be used as a vulcanizing shoe; a recess within the wall; a

heating element for heating said wall and posi! tioned adjacent to saidwall; a switch tor controlling the how of current through said heatingelement and posltionedexteriorly ofthe casing; a thermostatic elementpositioned in said recess so that said thermostatic element issubstantially between the heating element and the wall, said thermostatcontrolling the action of the switch; a member of insulating materialcovering the recess; a plate of conductive material oi' substantiallythe same shape as the heating element placed against said insulatingmember; anda second member of insulating mateing element; a thermostatfor controlling the operation of the switch, said thermostat beingpositioned within said recess so that it is substantially between theheating element and the wall iand having one end thereof xedlymounted tothe .relatively thick wall oflthe casing so that the thermostat isresponsive tothe temperature of the said wall. i

7. In an electric vulcanizer, a casing forming. a vulcanizer shoe on oneside thereof; a heating element disposed contiguous to the shoe on theunderside thereof; a switch mounted on the exterior of the casing; aterminal block including a pluralityx oi terminals electricallyconnected with the switch; electrical connecting means for the heatingelement extending through the casing through said casing, saidthermostat being disposed to trip said latch when the shoe reaches apredetermined temperature to allow the said resilient means to open saidswitch.

ESTEL C. RANEY.

